Abstract: A fuel cell system includes: a reformer generating a reformed gas using a raw material; a fuel cell generating electric power; a raw material supply passage; a hydro-desulfurizer operative to remove sulfur component in the raw material; a recycle passage through which the reformed gas is supplied to the raw material supply passage provided upstream of the hydro-desulfurizer; a temperature detector detecting a temperature of the hydro-desulfurizer; and a controller, wherein: when the temperature of the hydro-desulfurizer reaches a predetermined temperature, the controller increases a flow rate of the raw material from a predetermined flow rate by a flow rate corresponding to a flow rate of the recycled gas, and then, the controller starts supplying the recycled gas to the recycle passage; and after the recycled gas reaches an upstream end of the recycle passage, the controller returns the flow rate of the raw material to the predetermined flow rate.

Abstract: A fuel cell system comprises a fuel cell configured to generate electric power through a power generation reaction by using fuel supplied to an anode and cathode air supplied to a cathode; a cathode air heat exchanger configured to perform heat exchange between a cathode exhaust gas which is air discharged after the air has been used in the fuel cell and the air to be supplied to the cathode to transfer a part of heat energy of the cathode exhaust gas to the air; a desulfurization unit configured to remove a sulfur component from a raw material supplied to the desulfurization unit; and a reformer configured to generate a reformed gas which is the fuel from steam and the raw material from which the sulfur component has been removed by the desulfurization unit; and the cathode exhaust gas which has lost a part of the heat energy by the heat exchange in at least the cathode air heat exchanger, is supplied to the desulfurization unit, to heat the desulfurization unit by the heat energy of the cathode exhaust gas.

Abstract: In a fuel cell power generation system that includes a fuel cell that generates power by an electrochemical reaction with a supply of a fuel gas and an oxide gas, a control portion that controls the amount of power generated by the fuel cell, and a hot portion that is hot while the system is operating, the control portion and the hot portion are disposed separated from one another in the same package. Accordingly, even though the control portion and the hot portion are housed within the same main package, the control portion is not easily effected by the hot portion while the system is operating because it is separated from the hot portion. As a result, the control portion is able to perform its function well.

Abstract: A fuel gas processing apparatus includes a gas supply portion for supplying a fuel gas containing carbon monoxide and a catalytic combustion portion for catalytically oxidizing the fuel gas supplied from the gas supply portion. The fuel gas processing apparatus includes a carbon monoxide reduction portion for reducing the amount of carbon monoxide contained in the fuel gas before the fuel gas is supplied to the catalytic combustion portion to enhance combustibility of the catalytic combustion portion.

Abstract: One embodiment of the present invention provides a solid oxide fuel cell, which includes: an anode; a cathode; and an ionically conducting solid oxide electrolyte disposed between the anode and the cathode; wherein the solid oxide electrolyte includes at least one first region having a relatively high operating temperature and at least one second region having a relatively low operating temperature; and wherein the composition of the solid oxide electrolyte is different in the first and second regions. Other embodiments of the invention provide methods for making and using the fuel cell, and also the solid oxide electrolyte.

Abstract: In a fuel cell power generation system that includes a fuel cell that generates power by an electrochemical reaction with a supply of a fuel gas and an oxide gas, a control portion that controls the amount of power generated by the fuel cell, and a hot portion that is hot while the system is operating, the control portion and the hot portion are disposed separated from one another in the same package. Accordingly, even though the control portion and the hot portion are housed within the same main package, the control portion is not easily effected by the hot portion while the system is operating because it is separated from the hot portion. As a result, the control portion is able to perform its function well.